**************************************************************************
USACE / NAVFAC / AFCEC / NASA
UFGS-32 12 15.16 (November 2012)
-------------------------------Preparing Activity: USACE
New
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2016
**************************************************************************
SECTION TABLE OF CONTENTS
DIVISION 32 - EXTERIOR IMPROVEMENTS
SECTION 32 12 15.16
WARM-MIX ASPHALT AIRFIELD PAVING
11/12
PART 1
GENERAL
1.1
FULL PAYMENT
1.1.1
Method of Measurement
1.1.2
Basis of Payment
1.2
PERCENT PAYMENT
1.2.1
Mat and Joint Densities
1.2.2
Pay Factor Based on In-place Density
1.2.3
Payment Adjustment for Smoothness
1.2.4
Laboratory Air Voids and Theoretical Maximum Density
1.2.5
Mean Absolute Deviation
1.2.6
Pay Adjustment Based on Grade
1.3
REFERENCES
1.4
SYSTEM DESCRIPTION
1.4.1
Asphalt Mixing Plant
1.4.2
Hauling Equipment
1.4.3
Material Transfer Vehicle (MTV)
1.4.4
Asphalt Pavers
1.4.4.1
Receiving Hopper
1.4.4.2
Automatic Grade Controls
1.4.5
Rollers
1.5
SUBMITTALS
1.6
QUALITY ASSURANCE
1.6.1
Sublot Sampling
1.6.2
Additional Sampling and Testing
1.6.3
In-place Density
1.6.4
Surface Smoothness
1.6.4.1
Smoothness Requirements
1.6.4.2
Testing Method
1.7
ENVIRONMENTAL REQUIREMENTS
PART 2
PRODUCTS
2.1
AGGREGATES
2.1.1
Coarse Aggregate
2.1.2
Fine Aggregate
SECTION 32 12 15.16
Page 1
2.1.3
Mineral Filler
2.1.4
Aggregate Gradation
2.2
ASPHALT CEMENT BINDER
2.3
WMA TECHNOLOGIES/PRODUCTS
2.4
MIX DESIGN
2.4.1
JMF Requirements
2.4.2
Adjustments to JMF
2.5
RECYCLED WMA
2.5.1
RAP Aggregates and Asphalt Cement
2.5.2
RAP Mix
PART 3
EXECUTION
3.1
CONTRACTOR QUALITY CONTROL
3.1.1
General Quality Control Requirements
3.1.2
Testing Laboratory
3.1.3
Quality Control Testing
3.1.3.1
Asphalt Content
3.1.3.2
Aggregate Properties
3.1.3.3
Temperatures
3.1.3.4
Aggregate Moisture
3.1.3.5
Moisture Content of Mixture
3.1.3.6
Laboratory Air Voids, VMA, Marshall Stability and Flow
3.1.3.7
Moisture Susceptibility
3.1.3.8
In-Place Density
3.1.3.9
Grade and Smoothness
3.1.3.10
Additional Testing
3.1.3.11
QC Monitoring
3.1.4
Sampling
3.1.5
Control Charts
3.2
PREPARATION OF ASPHALT BINDER MATERIAL
3.3
PREPARATION OF MINERAL AGGREGATE
3.4
PREPARATION OF WARM-MIX ASPHALT MIXTURE
3.5
PREPARATION OF THE UNDERLYING SURFACE
3.6
TEST SECTION
3.6.1
Sampling and Testing for Test Section
3.6.2
Additional Test Sections
3.7
TESTING LABORATORY
3.8
TRANSPORTING AND PLACING
3.8.1
Transporting
3.8.2
Placing
3.9
COMPACTION OF MIXTURE
3.9.1
General
3.9.2
Segregation
3.10
JOINTS
3.10.1
Transverse Joints
3.10.2
Longitudinal Joints
3.10.3
WMA-Portland Cement Concrete Joints
-- End of Section Table of Contents --
SECTION 32 12 15.16
Page 2
**************************************************************************
USACE / NAVFAC / AFCEC / NASA
UFGS-32 12 15.16 (November 2012)
-------------------------------Preparing Activity: USACE
New
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2016
**************************************************************************
SECTION 32 12 15.16
WARM-MIX ASPHALT AIRFIELD PAVING
11/12
**************************************************************************
NOTE: This guide specification covers the
requirements for bituminous intermediate and wearing
courses (central-plant warm-mix) for airfields using
Marshall or Gyratory compaction method.
Adhere to UFC 1-300-02 Unified Facilities Guide
Specifications (UFGS) Format Standard when editing
this guide specification or preparing new project
specification sections. Edit this guide
specification for project specific requirements by
adding, deleting, or revising text. For bracketed
items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in
respective project, whether or not brackets are
present. Do not edit or rewrite the unbracketed
text without the express consent of the Corps of
Engineers Transportation Systems Center (TSMCX), the
Air Force major command (MAJCOM) paving engineers,
or the Naval Facilities Engineering Command (NAVFAC).
Comments, suggestions and recommended changes for
this guide specification are welcome and should be
submitted as a Criteria Change Request (CCR).
**************************************************************************
PART 1
GENERAL
**************************************************************************
NOTE: Modifications must be made to this guide
specification during conversion to a project
specification in accordance with the NOTES which are
located throughout the document. These NOTES are
instructions to the designer, and will not appear in
the project specification.
This guide specification only pertains to the
warm-mix asphalt (WMA) aspects of the project and
not to any surface preparation requirements dealing
SECTION 32 12 15.16
Page 3
with aggregate base courses, milling, or tack and
prime coats. Surface preparation requirements
should be covered by either including them in this
guide specification or by adding pertinent sections
to the project documents.
This specification utilizes a Quality Assurance and
Quality Control (QA/QC) construction management
philosophy. Quality Assurance refers to the actions
performed by the Government or designated
representative Engineer to assure the final product
meets the job requirements (see paragraph QUALITY
ASSURANCE). Results of QA testing are the basis for
pay. Quality Control refers to the actions of the
Contractor to monitor the construction and
production processes and to correct these processes
when out of control. Results of QC testing are
reported daily on the process control charts
maintained by the Contractor. Quality Control is
covered in paragraph CONTRACTOR QUALITY CONTROL.
**************************************************************************
1.1
1.1.1
FULL PAYMENT
Method of Measurement
**************************************************************************
NOTE: For unit-price contracts, include first
bracketed statements and delete the second set. For
lump sum contracts, delete the first bracketed
statements and include the second set. Lump sum
contracts should not be used when the job exceeds
1000 metric tons.
**************************************************************************
[The amount paid for will be the number of metric short tons of WMA mixture
used in the accepted work. WMA mixture shall be weighed after mixing, and
no separate payment will be made for weight of asphalt cement or other
additives incorporated herein.] [Measurement of the quantity of WMA, per
ton placed and accepted, shall be made for the purposes of assessing the
pay factors stipulated below.]
1.1.2
Basis of Payment
**************************************************************************
NOTE: For unit-price contracts, include first
bracketed statements and delete the second set. For
lump sum contracts, delete the first bracketed
statements and include the second set. Include
prescriptive unit price based on the
Government/Engineer estimate for payment
adjustment. lump sum contracts should not be used
when the job exceeds 1000 metric tons.
**************************************************************************
[Quantities of WMA, determined as specified above, will be paid for at
respective contract unit prices or at reduced prices adjusted in accordance
with paragraphs PERCENT PAYMENT and QUALITY ASSURANCE. Payment will
constitute full compensation for furnishing all materials, equipment,
SECTION 32 12 15.16
Page 4
plant, and tools; and for all labor and other incidentals necessary to
complete work required by this section of the specification.] [The measured
quantity of WMA will be paid for and included in the lump sum contract
price. If less than 100 percent payment is due based on the pay factors
stipulated in paragraph QUALITY ASSURANCE, a unit price of [_____] per ton
will be used for purposes of calculating the payment reduction.]
1.2
PERCENT PAYMENT
When a lot of material fails to meet the specification requirements for 100
percent pay as outlined in the following paragraphs, that lot shall be
removed and replaced, or accepted at a reduced price which will be computed
by multiplying the unit price by the lot's pay factor. The lot pay factor
is determined by taking the lowest computed pay factor based on either
laboratory air voids, in-place density, grade or smoothness (each discussed
below). Pay factors based on different criteria (i.e., laboratory air
voids and in-place density) of the same lot will not be multiplied together
to get a lower lot pay factor. At the end of the project, an average of
all lot pay factors will be calculated. If this average lot pay factor
exceeds 95.0 percent and no individual lot has a pay factor less than 75.1
percent, then the percent payment for the entire project will be 100
percent of the unit bid price. If the average lot pay factor is less than
95.0 percent, then each lot will be paid for at the unit price multiplied
by the lot's pay factor. For any lots which are less than 2000 metric short
tons, a weighted lot pay factor will be used to calculate the average lot
pay factor.
1.2.1
Mat and Joint Densities
The average in-place mat and joint densities are expressed as a percentage
of the average theoretical maximum density (TMD) for the lot. The average
TMD for each lot will be determined as the average TMD of the two random
samples per lot. The average in-place mat density and joint density for a
lot are determined and compared with Table 1 to calculate a single pay
factor per lot based on in-place density, as described below. First, a pay
factor for both mat density and joint density are determined from Table 1.
The area associated with the joint is then determined and will be
considered to be 3 m 10 feet wide times the length of completed
longitudinal construction joint in the lot. This area will not exceed the
total lot size. The length of joint to be considered will be that length
where a new lane has been placed against an adjacent lane of WMA pavement,
either an adjacent freshly paved lane or one paved at any time previously.
The area associated with the joint is expressed as a percentage of the
total lot area. A weighted pay factor for the joint is determined based on
this percentage (see example below). The pay factor for mat density and
the weighted pay factor for joint density is compared and the lowest
selected. This selected pay factor is the pay factor based on density for
the lot. When the TMD on both sides of a longitudinal joint is different,
the average of these two TMD will be used as the TMD needed to calculate
the percent joint density. Rejected lots shall be removed and replaced.
Rejected areas adjacent to longitudinal joints shall be removed 100 mm 4
inches into the cold (existing) lane. All density results for a lot will
be completed and reported within 24 hours after the construction of that
lot.
SECTION 32 12 15.16
Page 5
Total area of lot = 30,000 square feet. (4) Length of completed
longitudinal construction joint = 2000 feet.
a.
Step 1: Determine pay factor based on mat density and on joint
density, using Table 1:
Mat density of 93.2 percent = 98.3 pay factor.
Joint density of 91.5 percent = 97.3 pay factor.
b.
Step 2: Determine ratio of joint area (length of longitudinal joint x
10 ft) to mat area (total paved area in the lot): Multiply the length
of completed longitudinal construction joint by the specified 10 ft.
width and divide by the mat area (total paved area in the lot).
(2000 ft. x 10 ft.)/30000 sq.ft. = 0.6667 ratio of joint area to mat
area (ratio).
c.
Step 3: Weighted pay factor (wpf) for joint is determined as indicated
below:
wpf = joint pay factor + (100 - joint pay factor) (1 - ratio) wpf =
97.3 + (100-97.3) (1-.6667) = 98.2 percent
d.
Step 4: Compare weighted pay factor for joint density to pay factor for
mat density and select the smaller:
Pay factor for mat density: 98.3 percent.
joint density: 98.2 percent
Weighted pay factor for
Select the smaller of the two values as pay factor based on density:
98.2 percent
1.2.3
Payment Adjustment for Smoothness
a.
Straightedge Testing. Location and deviation from straightedge for all
measurements shall be recorded. When between 5.0 and 10.0 percent of
all measurements made within a lot exceed the tolerance specified in
paragraph Smoothness Requirements below, after any reduction of high
spots or removal and replacement, the computed pay factor for that lot
based on surface smoothness, will be 95 percent. When more than 10.0
percent of all measurements exceed the tolerance, the computed pay
factor will be 90 percent. When between 15.0 and 20.0 percent of all
measurements exceed the tolerance, the computed pay factor will be 75
percent. When 20.0 percent or more of the measurements exceed the
tolerance, the lot shall be removed and replaced at no additional cost
to the Government/Owner. Regardless of the above, any small individual
area with surface deviation which exceeds the tolerance given above by
more than 50 percent, shall be corrected by diamond grinding to meet
the specification requirements above or shall be removed and replaced
at no additional cost to the Government/Owner.
b.
Profilograph Testing. Location and data from all profilograph
measurements shall be recorded. When the Profile Index of a lot
exceeds the tolerance specified in paragraph Smoothness Requirements by
16 mm/km 1.0 inch/mile, but less than 32 mm/km 2.0 inches/mile, after
any reduction of high spots or removal and replacement, the computed
pay factor for that lot based on surface smoothness will be 95
percent. When the Profile Index exceeds the tolerance by 32 mm/km 2.0
SECTION 32 12 15.16
Page 7
Total area of lot = 30,000 square feet. (4) Length of completed
longitudinal construction joint = 2000 feet.
a.
Step 1: Determine pay factor based on mat density and on joint
density, using Table 1:
Mat density of 93.2 percent = 98.3 pay factor.
Joint density of 91.5 percent = 97.3 pay factor.
b.
Step 2: Determine ratio of joint area (length of longitudinal joint x
10 ft) to mat area (total paved area in the lot): Multiply the length
of completed longitudinal construction joint by the specified 10 ft.
width and divide by the mat area (total paved area in the lot).
(2000 ft. x 10 ft.)/30000 sq.ft. = 0.6667 ratio of joint area to mat
area (ratio).
c.
Step 3: Weighted pay factor (wpf) for joint is determined as indicated
below:
wpf = joint pay factor + (100 - joint pay factor) (1 - ratio) wpf =
97.3 + (100-97.3) (1-.6667) = 98.2 percent
d.
Step 4: Compare weighted pay factor for joint density to pay factor for
mat density and select the smaller:
Pay factor for mat density: 98.3 percent.
joint density: 98.2 percent
Weighted pay factor for
Select the smaller of the two values as pay factor based on density:
98.2 percent
1.2.3
Payment Adjustment for Smoothness
a.
Straightedge Testing. Location and deviation from straightedge for all
measurements shall be recorded. When between 5.0 and 10.0 percent of
all measurements made within a lot exceed the tolerance specified in
paragraph Smoothness Requirements below, after any reduction of high
spots or removal and replacement, the computed pay factor for that lot
based on surface smoothness, will be 95 percent. When more than 10.0
percent of all measurements exceed the tolerance, the computed pay
factor will be 90 percent. When between 15.0 and 20.0 percent of all
measurements exceed the tolerance, the computed pay factor will be 75
percent. When 20.0 percent or more of the measurements exceed the
tolerance, the lot shall be removed and replaced at no additional cost
to the Government/Owner. Regardless of the above, any small individual
area with surface deviation which exceeds the tolerance given above by
more than 50 percent, shall be corrected by diamond grinding to meet
the specification requirements above or shall be removed and replaced
at no additional cost to the Government/Owner.
b.
Profilograph Testing. Location and data from all profilograph
measurements shall be recorded. When the Profile Index of a lot
exceeds the tolerance specified in paragraph Smoothness Requirements by
16 mm/km 1.0 inch/mile, but less than 32 mm/km 2.0 inches/mile, after
any reduction of high spots or removal and replacement, the computed
pay factor for that lot based on surface smoothness will be 95
percent. When the Profile Index exceeds the tolerance by 32 mm/km 2.0
SECTION 32 12 15.16
Page 7
inches/mile, but less than 47 mm/km 3.0 inches/mile, the computed pay
factor will be 90 percent. When the Profile Index exceeds the
tolerance by 47 mm/km 3.0 inches/mile, but less than 63 mm/km 4.0
inches/mile, the computed pay factor will be 75 percent. When the
Profile Index exceeds the tolerance by 63 mm/km 4.0 inches/mile or
more, the lot shall be removed and replaced at no additional cost to
the Government/Owner. Regardless of the above, any small individual
area with surface deviation which exceeds the tolerance given above by
more than 79 mm/km 5.0 inches/mile or more, shall be corrected by
grinding to meet the specification requirements above or shall be
removed and replaced at no additional cost to the Government/Owner.
1.2.4
Laboratory Air Voids and Theoretical Maximum Density
Laboratory air voids will be calculated in accordance with ASTM D3203/D3203M
by determining the density of each lab compacted specimen using the
laboratory-prepared, thoroughly dry method in ASTM D2726/D2726M and
determining the theoretical maximum density (TMD) of every other sublot
sample using ASTM D2041/D2041M. Laboratory air void calculations for each
sublot will use the latest theoretical maximum density values obtained,
either for that sublot or the previous sublot. The mean absolute deviation
of the four laboratory air void contents (one from each sublot) from the
JMF air void content will be evaluated and a pay factor determined from
Table 2. All laboratory air void tests will be completed and reported
within 24 hours after completion of construction of each lot. The TMD is
also used for computation of compaction, as required in paragraph: Mat and
Joint Densities above.
1.2.5
Mean Absolute Deviation
An example of the computation of mean absolute deviation for laboratory air
voids is as follows: Assume that the laboratory air voids are determined
from 4 random samples of a lot (where 3 specimens were compacted from each
sample). The average laboratory air voids for each sublot sample are
determined to be 3.5, 3.0, 4.0, and 3.7. Assume that the target air voids
from the JMF is 4.0. The mean absolute deviation is then:
Mean Absolute Deviation = (|3.5 - 4.0| + |3.0 - 4.0| + |4.0 - 4.0| + |3.7 4.0|)/4
= (0.5 + 1.0 + 0.0 + 0.3)/4 = (1.8)/4 = 0.45
The mean absolute deviation for laboratory air voids is determined to be
0.45. It can be seen from Table 2 that the lot's pay factor based on
laboratory air voids, is 100 percent.
Table 2.
Pay Factor Based on Laboratory Air Voids
Mean Absolute Deviation of Lab Air Voids from JMF
Pay Factor, Percent
O.60 or less
100
0.61 - 0.80
98
0.81 - 1.00
95
SECTION 32 12 15.16
Page 8
Table 2.
Pay Factor Based on Laboratory Air Voids
Mean Absolute Deviation of Lab Air Voids from JMF
Pay Factor, Percent
1.01 - 1.20
90
Above 1.20
reject (0)
1.2.6
Pay Adjustment Based on Grade
**************************************************************************
NOTE: The grade and surface smoothness requirements
specified below are for the final wearing surface
only. If there is a requirement to test and control
the grade and smoothness for the intermediate
courses, i.e., when the intermediate courses will be
exposed to traffic, slight modifications to this
specification will be required.
**************************************************************************
Within 5 working days after completion of a particular lot incorporating
the final wearing course, test the final wearing surface of the pavement
for conformance with specified plan grade requirements. All testing shall
be performed in the presence of the Contracting Officer/Engineer. The
final wearing surface of pavement shall conform to the elevations and cross
sections shown and shall vary not more than 9 mm 0.03 foot for runways or
15 mm 0.05 foot for taxiways and aprons from the plan grade established and
approved at site of work. Finished surfaces at juncture with other
pavements shall coincide with finished surfaces of abutting pavements.
Deviation from the plan elevation will not be permitted in areas of
pavements where closer conformance with planned elevation is required for
the proper functioning of drainage and other appurtenant structures
involved. The grade will be determined by running lines of levels at
intervals of 7.6 m 25 feet, or less, longitudinally and transversely, to
determine the elevation of the completed pavement surface. Detailed notes
of the results of the testing shall be kept and a copy furnished to the
Government/Engineer immediately after each day's testing. When more than 5
percent of all measurements made within a lot are outside the 9 or 15 mm
0.03 or 0.05 foot tolerance, the pay factor based on grade for that lot
will be 95 percent. In areas where the grade exceeds the tolerance by more
than 50 percent, remove the surface lift full depth; and replace the lift
with WMA to meet specification requirements, at no additional cost to the
Government/Owner. Diamond grinding may be used to remove high spots to
meet grade requirements. Skin patching for correcting low areas or planing
or milling for correcting high areas will not be permitted.
1.3
REFERENCES
**************************************************************************
NOTE: This paragraph is used to list the
publications cited in the text of the guide
specification. The publications are referred to in
the text by basic designation only and listed in
this paragraph by organization, designation, date,
and title.
Use the Reference Wizard's Check Reference feature
when you add a RID outside of the Section's
SECTION 32 12 15.16
Page 9
Reference
reference
Reference
the issue
Article to automatically place the
in the Reference Article. Also use the
Wizard's Check Reference feature to update
dates.
References not used in the text will automatically
be deleted from this section of the project
specification when you choose to reconcile
references in the publish print process.
**************************************************************************
The publications listed below form a part of this specification to the
extent referenced. The publications are referred to within the text by the
basic designation only.
AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS
(AASHTO)
AASHTO M 156
(2013) Standard Specification for
Requirements for Mixing Plants for
Hot-Mixed, Hot-Laid Bituminous Paving
Mixtures
AASHTO M 320
(2010; 2015) Standard Specification for
Performance-Graded Asphalt Binder
AASHTO T 308
(2010; R 2015) Standard Method of Test for
Determining the Asphalt Binder Content of
Hot Mix Asphalt (HMA) by the Ignition
Method
AASHTO T 329
(2015) Standard Test Method for Moisture
Content of Hot Mix Asphalt (HMA) by Oven
Method
ASPHALT INSTITUTE (AI)
AI MS-2
(2015) Asphalt Mix Design Methods
ASTM INTERNATIONAL (ASTM)
ASTM C117
(2013) Standard Test Method for Materials
Finer than 75-um (No. 200) Sieve in
Mineral Aggregates by Washing
ASTM C1252
(2006) Standard Test Methods for
Uncompacted Void Content of Fine Aggregate
(as Influenced by Particle Shape, Surface
Texture, and Grading)
ASTM C127
(2015) Standard Test Method for Density,
Relative Density (Specific Gravity), and
Absorption of Coarse Aggregate
ASTM C128
(2015) Standard Test Method for Density,
Relative Density (Specific Gravity), and
Absorption of Fine Aggregate
ASTM C131/C131M
(2014) Standard Test Method for Resistance
SECTION 32 12 15.16
Page 10
to Degradation of Small-Size Coarse
Aggregate by Abrasion and Impact in the
Los Angeles Machine
ASTM C136/C136M
(2014) Standard Test Method for Sieve
Analysis of Fine and Coarse Aggregates
ASTM C142/C142M
(2010) Standard Test Method for Clay Lumps
and Friable Particles in Aggregates
ASTM C29/C29M
(2009) Standard Test Method for Bulk
Density ("Unit Weight") and Voids in
Aggregate
ASTM C566
(2013) Standard Test Method for Total
Evaporable Moisture Content of Aggregate
by Drying
ASTM C88
(2013) Standard Test Method for Soundness
of Aggregates by Use of Sodium Sulfate or
Magnesium Sulfate
ASTM D140/D140M
(2015) Standard Practice for Sampling
Bituminous Materials
ASTM D1461
(2011) Moisture or Volatile Distillates in
Bituminous Paving Mixtures
ASTM D2041/D2041M
(2011) Theoretical Maximum Specific
Gravity and Density of Bituminous Paving
Mixtures
ASTM D2172/D2172M
(2011) Quantitative Extraction of Bitumen
from Bituminous Paving Mixtures
ASTM D2419
(2014) Sand Equivalent Value of Soils and
Fine Aggregate
ASTM D242/D242M
(2009; R 2014) Mineral Filler for
Bituminous Paving Mixtures
ASTM D2489/D2489M
(2008) Estimating Degree of Particle
Coating of Bituminous-Aggregate Mixtures
ASTM D2726/D2726M
(2014) Bulk Specific Gravity and Density
of Non-Absorptive Compacted Bituminous
Mixtures
ASTM D3203/D3203M
(2011) Percent Air Voids in Compacted
Dense and Open Bituminous Paving Mixtures
ASTM D3381/D3381M
(2013) Viscosity-Graded Asphalt Cement for
Use in Pavement Construction
ASTM D3665
(2012) Random Sampling of Construction
Materials
ASTM D3666
(2013) Standard Specification for Minimum
Requirements for Agencies Testing and
SECTION 32 12 15.16
Page 11
Inspecting Road and Paving Materials
ASTM D4125/D4125M
(2010) Asphalt Content of Bituminous
Mixtures by the Nuclear Method
ASTM D4791
(2010) Flat Particles, Elongated
Particles, or Flat and Elongated Particles
in Coarse Aggregate
ASTM D4867/D4867M
(2009; R 2014) Effect of Moisture on
Asphalt Concrete Paving Mixtures
ASTM D5444
(2015) Mechanical Size Analysis of
Extracted Aggregate
ASTM D6307
(2010) Asphalt Content of Hot Mix Asphalt
by Ignition Method
ASTM D6925
(2014) Standard Test Method for
Preparation and Determination of the
Relative Density of Hot Mix Asphalt (HMA)
Specimens by Means of the Superpave
Gyratory Compactor
ASTM D6926
(2010) Standard Practice for Preparation
of Bituminous Specimens Using Marshall
Apparatus
ASTM D6927
(2015) Standard Test Method for Marshall
Stability and Flow of Bituminous Mixtures
ASTM D946/D946M
(2009a) Penetration-Graded Asphalt Cement
for Use in Pavement Construction
ASTM D979/D979M
(2015) Sampling Bituminous Paving Mixtures
STATE OF CALIFORNIA DEPARTMENT OF TRANSPORTATION (CALTRANS)
CTM 526
(2002) Operation of California
Profilograph and Evaluation of Profiles
U.S. ARMY CORPS OF ENGINEERS (USACE)
COE CRD-C 171
1.4
(1995) Standard Test Method for
Determining Percentage of Crushed
Particles in Aggregate
SYSTEM DESCRIPTION
Perform the work consisting of pavement courses composed of mineral
aggregate and asphalt material heated and mixed in a central mixing plant
and placed on a prepared course. WMA designed and constructed in
accordance with this section shall conform to the lines, grades,
thicknesses, and typical cross sections shown on the drawings. Construct
each course to the depth, section, or elevation required by the drawings
and rolled, finished, and approved before the placement of the next
course. Submit proposed Placement Plan, indicating lane widths,
longitudinal joints, and transverse joints for each course or lift.
SECTION 32 12 15.16
Page 12
1.4.1
Asphalt Mixing Plant
Plants used for the preparation of WMA shall conform to the requirements of
AASHTO M 156 with the following changes:
a.
Truck Scales. Weigh the asphalt mixture on approved scales furnished
by the Contractor, or on certified public scales at the Contractor's
expense. Scales shall be inspected and sealed at least annually by an
approved calibration laboratory.
b.
Testing Facilities. Provide laboratory facilities at the plant for the
use of the Government's Engineer's acceptance testing and the
Contractor's quality control testing.
c.
Inspection of Plant. The Contracting Officer Engineer shall have
access at all times, to all areas of the plant for checking adequacy of
equipment; inspecting operation of the plant; verifying weights,
proportions, and material properties; checking the temperatures
maintained in the preparation of the mixtures and for taking samples.
Provide assistance as requested, for the Government Engineer to procure
any desired samples.
d.
Storage Bins. The asphalt mixture may be stored in non-insulated
storage bins for a period of time not exceeding 3 hours. The asphalt
mixture may be stored in insulated storage bins for a period of time
not exceeding 8 hours. The mix drawn from bins shall meet the same
requirements as mix loaded directly into trucks.
1.4.2
Hauling Equipment
Trucks used for hauling WMA shall have tight, clean, and smooth metal
beds. To prevent the mixture from adhering to them, the truck beds shall
be lightly coated with a minimum amount of paraffin oil, lime solution, or
other approved material. Petroleum based products shall not be used as a
release agent. Each truck shall have a suitable cover to protect the
mixture from adverse weather. When necessary to ensure that the mixture
will be delivered to the site at the specified temperature, truck beds
shall be insulated or heated and covers (tarps) shall be securely fastened.
1.4.3
Material Transfer Vehicle (MTV)
**************************************************************************
NOTE: A Material Transfer Vehicle (MTV) is required
for runway and taxiway construction. The use of an
MTV is optional for shoulder construction.
**************************************************************************
Material transfer Vehicles shall be required due to the improvement in
smoothness and decrease in both physical and thermal segregation. To
transfer the material from the hauling equipment to the paver, use a
self-propelled, material transfer vehicle that can deliver material to the
paver without making contact with the paver. The MTV shall be able to move
back and forth between the hauling equipment and the paver providing
material transfer to the paver, while allowing the paver to operate at a
constant speed. The Material Transfer Vehicle will have remixing and
storage capability to prevent physical and thermal segregation.
1.4.4
Asphalt Pavers
Mechanical spreading and finishing equipment shall consist of a
SECTION 32 12 15.16
Page 13
Table 3.
Straightedge Surface Smoothness--Pavements
Pavement Category
All other airfields and
helicopter paved areas
b.
Direction of Testing
Tolerance, mm inches
Longitudinal
61/4
Transverse
61/4
Profilograph Testing: The finished surfaces of the pavements shall
have no abrupt change of 3 mm 1/8 inch or more, and all pavement shall
have a Profile Index not greater than specified in Table 4 when tested
with an approved California-type profilograph. If the extent of the
pavement in either direction is less than 60 m 200 feet, that direction
shall be tested by the straightedge method and shall meet requirements
specified above.
Table 4.
Profilograph Surface Smoothness--Pavements
Pavement Category
Runways
Taxiways
Shoulders (outside edge
strip)
Direction of Testing
Maximum Specified Profile
Index (mm/kminch/mile)
Longitudinal
1107
Transverse
(Use Straightedge)
Longitudinal
1409
Transverse
(Use Straightedge)
Transverse
(Use Straightedge)
Longitudinal
Not required
Calibration Hardstands and
Compass Swinging Bases
All Other Airfield and
Helicopter Paved Areas
1.6.4.2
(Use Straightedge)
Longitudinal
1409
Transverse
1409
Testing Method
After the final rolling, but not later than 24 hours after placement, the
surface of the pavement in each entire lot shall be tested in such a manner
as to reveal all surface irregularities exceeding the tolerances specified
above. Separate testing of individual sublots is not required. If any
pavement areas are diamond ground, these areas shall be retested
immediately after grinding. The area corrected by grinding shall not
exceed 10 percent of the total area of the lot. The entire area of the
pavement shall be tested in both a longitudinal and a transverse direction
on parallel lines. The transverse lines shall be 4.5 m 15 feet or less
SECTION 32 12 15.16
Page 19
apart, as directed. The longitudinal lines shall be at the centerline of
each paving lane for lines less than 6.1 m 20 feet and at the third points
for lanes 6.1 m 20 feet or greater. Other areas having obvious deviations
shall also be tested. Longitudinal testing lines shall be continuous
across all joints.
a.
Straightedge Testing. The straightedge shall be held in contact with
the surface and moved ahead one-half the length of the straightedge for
each successive measurement. The amount of surface irregularity shall
be determined by placing the freestanding (unleveled) straightedge on
the pavement surface and allowing it to rest upon the two highest spots
covered by its length, and measuring the maximum gap between the
straightedge and the pavement surface in the area between these two
high points.
b.
Profilograph Testing. Profilograph testing shall be performed using
approved equipment and procedures described in CTM 526. The equipment
shall utilize electronic recording and automatic computerized reduction
of data to indicate "must-grind" bumps and the Profile Index for the
pavement. The "blanking band" shall be 5 mm 0.2 inches wide and the
"bump template" shall span 25 mm 1 inch with an offset of 10 mm 0.4 inch.
The profilograph shall be operated by an approved, factory-trained
operator on the alignments specified above. A copy of the reduced
tapes shall be furnished the Government Engineer at the end of each
day's testing.
c.
Bumps ("Must Grind" Areas). Any bumps ("must grind" areas) shown on
the profilograph trace which exceed 10 mm 0.4 inch in height shall be
reduced by diamond grinding until they do not exceed 7.5 mm 0.3 inch
when retested. Such grinding shall be tapered in all directions to
provide smooth transitions to areas not requiring grinding. The
following will not be permitted: (1) skin patching for correcting low
areas, (2) planing or milling for correcting high areas. At the
Contractor's option, pavement areas, including ground areas, may be
rechecked with the profilograph in order to record a lower Profile
Index.
1.7
ENVIRONMENTAL REQUIREMENTS
**************************************************************************
NOTE: The temperature requirements in Table 5 are
included to avoid problems with the Contractor
achieving density because the mix cools too fast.
Waivers to these requirements, for isolated
incidences during production, are applicable if the
density requirements are still met.
**************************************************************************
The WMA shall not be placed upon a wet surface or when the surface
temperature of the underlying course is less than 4 degrees C 40 degrees F.
PART 2
2.1
PRODUCTS
AGGREGATES
Aggregates shall consist of crushed stone, crushed gravel, crushed slag,
screenings, natural sand and mineral filler, as required. The portion of
material retained on the 4.75 mm No. 4 sieve is coarse aggregate. The
portion of material passing the 4.75 mm No. 4 sieve and retained on the
SECTION 32 12 15.16
Page 20
SD-06 Test Reports
Aggregates; G[, [_____]]
QC Monitoring
SD-07 Certificates
Asphalt Cement Binder; G[, [_____]]
Testing Laboratory
WMA Additive
1.6
QUALITY ASSURANCE
**************************************************************************
NOTE: It is highly recommended to keep the
Government Engineer's QA testing separate and
distinct from the Contractor's QC testing. However,
it is recognized that in-house testing capability to
provide the QA testing required by this section will
not always be available; in this case, it is
recommended that an independent material testing
company be hired to provide the QA testing for the
project. The cost of this testing to assure good
long-term performance is very small relative to the
overall cost of the construction, and especially
compared to the cost of a pavement failure.
Although not recommended, this guide specification
may be modified to require the Contractor to hire an
independent material testing laboratory to perform
the QA testing listed in this section. The results
would need to be forwarded daily to the Contracting
Officer Engineer as the basis for acceptance and
pay. This should only be done if there is no way of
hiring an independent testing laboratory to perform
the QA testing.
The QA testing program includes material tests to
determine laboratory air voids and in-place density,
which are needed to determine percent payment. The
project engineer may choose to have additional tests
conducted by the QA test agency to monitor aggregate
gradation, asphalt content, Marshall stability and
flow. These tests would serve as a check to the
Contractor's QC testing. Marshall stability and
flow could be done at minimal cost since the
specimens have to be made anyway for laboratory air
void determination. This additional testing, if
conducted, is not included as part of this
specification since the parameters are not used as a
basis of pay.
For projects with less than 2000 total metric tons,
the entire project can be considered as a single
lot. In this case, sublot sampling could occur over
several days' production, which could lead to higher
sublot variability.
**************************************************************************
SECTION 32 12 15.16
Page 16
The Government Engineer's quality assurance (QA) program for this project
is separate and distinct from the Contractor's quality control (QC) program
specified in Part 3. Testing for acceptability of work will be performed
by the Government Engineer or by an independent laboratory hired by the
Contracting Officer Engineer, except for grade and smoothness testing which
shall be performed by the Contractor. Acceptance of the plant produced mix
and in-place requirements will be on a lot to lot basis. A standard lot
for all requirements will be equal to 2000 metric short tons. Where
appropriate, adjustment in payment for individual lots of WMA will be made
based on in-place density, laboratory air voids, grade and smoothness in
accordance with the following paragraphs. Grade and surface smoothness
determinations will be made on the lot as a whole. Exceptions or
adjustments to this will be made in situations where the mix within one lot
is placed as part of both the intermediate and surface courses, thus grade
and smoothness measurements for the entire lot cannot be made. In order to
evaluate laboratory air voids and in-place (field) density, each lot will
be divided into four equal sublots.
1.6.1
Sublot Sampling
One random mixture sample for determining laboratory air voids, theoretical
maximum density, and for any additional testing the Contracting Officer
Engineer desires, will be taken from a loaded truck delivering mixture to
each sublot, or other appropriate location for each sublot. All samples
will be selected randomly, using commonly recognized methods of assuring
randomness conforming to ASTM D3665 and employing tables of random numbers
or computer programs. Laboratory air voids will be determined from three
laboratory compacted specimens of each sublot sample in accordance with
ASTM D6926. The specimens will be compacted within 2 hours of the time the
mixture was loaded into trucks at the asphalt plant. Samples will not be
reheated prior to compaction and insulated containers will be used as
necessary to maintain the temperature.
1.6.2
Additional Sampling and Testing
The Contracting Officer Engineer reserves the right to direct additional
samples and tests for any area which appears to deviate from the
specification requirements. The cost of any additional testing will be
paid for by the Government/Owner. Testing in these areas will be treated
as a separate lot. Payment will be made for the quantity of WMA
represented by these tests in accordance with the provisions of this
section.
1.6.3
In-place Density
For determining in-place density, one random core (100 mm 4 inches or 150 mm
6 inches in diameter) will be taken by the Government Engineer from the
mat (interior of the lane) of each sublot, and one random core will be
taken from the joint (immediately over joint) of each sublot, in accordance
with ASTM D979/D979M. Each random core will be full thickness of the layer
being placed. When the random core is less than 25 mm 1 inch thick, it
will not be included in the analysis. In this case, another random core
will be taken. After air drying to meet the requirements for
laboratory-prepared, thoroughly dry specimens, cores obtained from the mat
and from the joints will be used for in-place density determination in
accordance with ASTM D2726/D2726M.
SECTION 32 12 15.16
Page 17
1.6.4
Surface Smoothness
**************************************************************************
NOTE: Edit these paragraphs as appropriate to the
project. It is desired to restrict surface
smoothness testing and evaluation to either
straightedge method or profilograph method. Retain
the one and delete the other; otherwise, retain both
as a Contractor's option. Generally, designer
should require use of the profilograph method. If
the profilograph method is allowed, and there are
areas with dimensions less than 60 m 200 feet in any
direction, part of the straightedge method must be
retained for these short runs.
**************************************************************************
Use [one] [both] of the following methods to test and evaluate surface
smoothness of the finished surface of the pavement final grade. All
testing shall be performed in the presence of the Contracting Officer
Engineer. Detailed notes of the results of the testing shall be kept and a
copy furnished to the Government Engineer immediately after each day's
testing. The profilograph method shall be used for all longitudinal and
transverse testing, except where the runs would be less than 60 m 200 feet
in length and the ends where the straightedge shall be used. Where
drawings show required deviations from a plane surface (crowns, drainage
inlets, etc.), the surface shall be finished to meet the approval of the
Contracting Officer Engineer.
1.6.4.1
a.
Smoothness Requirements
Straightedge Testing: The finished surfaces of the pavements shall
have no abrupt change of 3 mm 1/8 inch or more, and all pavements shall
be within the tolerances specified in Table 3 when checked with an
approved 4 m 12 foot straightedge.
Table 3.
Straightedge Surface Smoothness--Pavements
Pavement Category
Runways and taxiway
Shoulders (outside edge
strip)
Calibration hardstands and
compass swinging bases
Direction of Testing
Tolerance, mm inches
Longitudinal
31/8
Transverse
61/4
Transverse
61/4
Longitudinal
Not required
Longitudinal
31/8
Transverse
31/8
SECTION 32 12 15.16
Page 18
Table 3.
Straightedge Surface Smoothness--Pavements
Pavement Category
All other airfields and
helicopter paved areas
b.
Direction of Testing
Tolerance, mm inches
Longitudinal
61/4
Transverse
61/4
Profilograph Testing: The finished surfaces of the pavements shall
have no abrupt change of 3 mm 1/8 inch or more, and all pavement shall
have a Profile Index not greater than specified in Table 4 when tested
with an approved California-type profilograph. If the extent of the
pavement in either direction is less than 60 m 200 feet, that direction
shall be tested by the straightedge method and shall meet requirements
specified above.
Table 4.
Profilograph Surface Smoothness--Pavements
Pavement Category
Runways
Taxiways
Shoulders (outside edge
strip)
Direction of Testing
Maximum Specified Profile
Index (mm/kminch/mile)
Longitudinal
1107
Transverse
(Use Straightedge)
Longitudinal
1409
Transverse
(Use Straightedge)
Transverse
(Use Straightedge)
Longitudinal
Not required
Calibration Hardstands and
Compass Swinging Bases
All Other Airfield and
Helicopter Paved Areas
1.6.4.2
(Use Straightedge)
Longitudinal
1409
Transverse
1409
Testing Method
After the final rolling, but not later than 24 hours after placement, the
surface of the pavement in each entire lot shall be tested in such a manner
as to reveal all surface irregularities exceeding the tolerances specified
above. Separate testing of individual sublots is not required. If any
pavement areas are diamond ground, these areas shall be retested
immediately after grinding. The area corrected by grinding shall not
exceed 10 percent of the total area of the lot. The entire area of the
pavement shall be tested in both a longitudinal and a transverse direction
on parallel lines. The transverse lines shall be 4.5 m 15 feet or less
SECTION 32 12 15.16
Page 19
apart, as directed. The longitudinal lines shall be at the centerline of
each paving lane for lines less than 6.1 m 20 feet and at the third points
for lanes 6.1 m 20 feet or greater. Other areas having obvious deviations
shall also be tested. Longitudinal testing lines shall be continuous
across all joints.
a.
Straightedge Testing. The straightedge shall be held in contact with
the surface and moved ahead one-half the length of the straightedge for
each successive measurement. The amount of surface irregularity shall
be determined by placing the freestanding (unleveled) straightedge on
the pavement surface and allowing it to rest upon the two highest spots
covered by its length, and measuring the maximum gap between the
straightedge and the pavement surface in the area between these two
high points.
b.
Profilograph Testing. Profilograph testing shall be performed using
approved equipment and procedures described in CTM 526. The equipment
shall utilize electronic recording and automatic computerized reduction
of data to indicate "must-grind" bumps and the Profile Index for the
pavement. The "blanking band" shall be 5 mm 0.2 inches wide and the
"bump template" shall span 25 mm 1 inch with an offset of 10 mm 0.4 inch.
The profilograph shall be operated by an approved, factory-trained
operator on the alignments specified above. A copy of the reduced
tapes shall be furnished the Government Engineer at the end of each
day's testing.
c.
Bumps ("Must Grind" Areas). Any bumps ("must grind" areas) shown on
the profilograph trace which exceed 10 mm 0.4 inch in height shall be
reduced by diamond grinding until they do not exceed 7.5 mm 0.3 inch
when retested. Such grinding shall be tapered in all directions to
provide smooth transitions to areas not requiring grinding. The
following will not be permitted: (1) skin patching for correcting low
areas, (2) planing or milling for correcting high areas. At the
Contractor's option, pavement areas, including ground areas, may be
rechecked with the profilograph in order to record a lower Profile
Index.
1.7
ENVIRONMENTAL REQUIREMENTS
**************************************************************************
NOTE: The temperature requirements in Table 5 are
included to avoid problems with the Contractor
achieving density because the mix cools too fast.
Waivers to these requirements, for isolated
incidences during production, are applicable if the
density requirements are still met.
**************************************************************************
The WMA shall not be placed upon a wet surface or when the surface
temperature of the underlying course is less than 4 degrees C 40 degrees F.
PART 2
2.1
PRODUCTS
AGGREGATES
Aggregates shall consist of crushed stone, crushed gravel, crushed slag,
screenings, natural sand and mineral filler, as required. The portion of
material retained on the 4.75 mm No. 4 sieve is coarse aggregate. The
portion of material passing the 4.75 mm No. 4 sieve and retained on the
SECTION 32 12 15.16
Page 20
0.075 mm No. 200 sieve is fine aggregate. The portion passing the 0.075 mm
No. 200 sieve is defined as mineral filler. Submit sufficient materials to
produce 90 kg 200 lb of blended mixture for mix design verification. All
aggregate test results and samples shall be submitted to the Contracting
Officer Engineer at least 14 days prior to start of construction.
Aggregate testing shall have been performed within 90 days of performing
the mix design.
2.1.1
Coarse Aggregate
**************************************************************************
NOTE: The requirement for sulfate soundness
(requirement b., below) may be deleted in climates
where freeze-thaw does not occur. However, in those
areas where freeze-thaw does not occur, requirement
b. should remain if experience has shown that this
test separates good performing aggregates from bad
performing aggregates. This requirement should be
retained for all Navy projects.
Percentage of Wear (ASTM C131/C131M) must not exceed
40. Aggregates with a higher percentage of wear may
be specified, provided a satisfactory record under
similar conditions of service and exposure has been
demonstrated.
**************************************************************************
Coarse aggregate shall consist of sound, tough, durable particles, free
from films of material that would prevent thorough coating and bonding with
the asphalt material and free from organic matter and other deleterious
substances. The coarse aggregate particles shall meet the following
requirements:
a.
The percentage of loss shall not be greater than 40 [_____] percent
after 500 revolutions when tested in accordance with ASTM C131/C131M.
b.
The sodium sulfate soundness loss shall not exceed 12 percent, or the
magnesium sulfate soundness loss shall not exceed 18 percent after five
cycles when tested in accordance with ASTM C88.
c.
At least 75 percent by weight of coarse aggregate shall have at least
two or more fractured faces when tested in accordance with COE CRD-C 171.
Fractured faces shall be produced by crushing.
d.
The particle shape shall be essentially cubical and the aggregate shall
not contain more than 20 percent, by weight, of flat and elongated
particles (3:1 ratio of maximum to minimum) when tested in accordance
with ASTM D4791.
e.
Slag shall be air-cooled, blast furnace slag, and shall have a
compacted weight of not less than 1200 kg/cubic meter 75 lb/cu ft when
tested in accordance with ASTM C29/C29M.
f.
Clay lumps and friable particles shall not exceed 0.3 percent, by
weight, when tested in accordance with ASTM C142/C142M.
2.1.2
Fine Aggregate
**************************************************************************
SECTION 32 12 15.16
Page 21
NOTE: The lower limit for uncompacted void content
(requirement c., below) should be set at 45 for fine
aggregate angularity unless local experiences
indicate that a lower value can be used. There are
some aggregates which have a good performance record
and have an uncompacted void content less than 45.
In no case should the limit be set less than 43.
**************************************************************************
Fine aggregate shall consist of clean, sound, tough, durable particles.
The aggregate particles shall be free from coatings of clay, silt, or any
objectionable material and shall contain no clay balls. The fine aggregate
particles shall meet the following requirements:
a.
The quantity of natural sand (noncrushed material) added to the
aggregate blend shall not exceed 15 percent by weight of total
aggregate.
b.
The individual fine aggregate sources shall have a sand equivalent
value greater than 45 when tested in accordance with ASTM D2419.
c.
The fine aggregate portion of the blended aggregate shall have an
uncompacted void content greater than 45.0 percent when tested in
accordance with ASTM C1252 Method A.
d.
Clay lumps and friable particles shall not exceed 0.3 percent, by
weight, when tested in accordance with ASTM C142/C142M.
2.1.3
Mineral Filler
Mineral filler shall be nonplastic material meeting the requirements of
ASTM D242/D242M.
2.1.4
Aggregate Gradation
**************************************************************************
NOTE: Delete from Table 5, the gradations that will
not be used as a part of this project. Generally,
the layer thickness should be at least 75 mm 3 inches
for gradation 1, 50 mm 2 inches for gradation 2 and
37 mm 1.5 inches for gradation 3 shown in Table 6.
Use of gradation 1 must be limited to intermediate
courses. Gradation 2 is suitable for intermediate
and surface courses. Use of gradation 3 must be
limited to shoulders and leveling courses. Do not
use gradation 1 for surface courses.
**************************************************************************
The combined aggregate gradation shall conform to gradations specified in
Table 5, when tested in accordance with ASTM C136/C136M and ASTM C117, and
shall not vary from the low limit on one sieve to the high limit on the
adjacent sieve or vice versa, but grade uniformly from coarse to fine. The
JMF shall be within the specification limits; however, the gradation can
exceed the limits when the allowable deviation from the JMF shown in Tables
8 and 9 are applied.
SECTION 32 12 15.16
Page 22
Table 5.
Aggregate Gradations
Gradation 1
Gradation 2
Gradation 3
Sieve Size, mm inch
Percent Passing by
Mass
Percent Passing by
Mass
Percent Passing by
Mass
25.01
100
---
---
19.03/4
90-100
100
---
12.51/2
68-88
90-100
100
9.53/8
60-82
69-89
90-100
4.75No. 4
45-67
53-73
58-78
2.36No. 8
32-54
38-60
40-60
1.18No. 16
22-44
26-48
28-48
0.60No. 30
15-35
18-38
18-38
0.30No. 50
9-25
11-27
11-27
0.15No. 100
6-18
6-18
6-18
0.075No. 200
3-6
3-6
3-6
2.2
ASPHALT CEMENT BINDER
**************************************************************************
NOTE: Performance Graded (PG) asphalt binders
should be specified wherever available. The same
grade PG binder used by the state highway department
in the area should be considered as the base grade
for the project (e.g. the grade typically specified
in that specific location for dense graded mixes on
highways with design ESALS less than 10 million).
The exception would be that grades with a low
temperature higher than PG XX-22 should not be used
(e.g. PG XX-16 or PG XX-10), unless the Engineer has
had successful experience with them.
Typically, rutting is not a problem on airport
pavements. However, at airports with a history of
stacking on end of runways and taxiway areas,
rutting has accrued due to the slow speed of loading
on the pavement. If there has been rutting on the
project or it is anticipated that stacking may
accrue during the design life of the project, then
the following grade "bumping" should be applied for
the top 125 mm 5 inches of paving in the end of
runway and taxiway areas: for aircraft tire pressure
between 0.7 and 1.4 MPa 100 and 200 psi, increase
the high temperature one grade; for aircraft tire
SECTION 32 12 15.16
Page 23
pressure greater than 1.4 MPa 200 psi, increase the
high temperature two grades.
For Navy projects, a high temperature increase of
two grades is required. Each grade adjustment is 6
degrees C. Polymer Modified Asphalt, PMA, has shown
to perform very well in these areas.
The low temperature grade should remain the same.
The Engineer may lower the low temperature grade to
comply with the recommendations of the FHWA's
software program "LTPPBind", if it is believed to be
appropriate.
**************************************************************************
Asphalt cement binder shall conform to AASHTO M 320 Performance Grade (PG)
[_____]. [As an alternate, ASTM D3381/D3381M Table 2, Viscosity Grade
[_____] or ASTM D946/D946M Penetration Grade [_____] may be used]. Test
data indicating grade certification shall be provided by the supplier at
the time of delivery of each load to the mix plant. When WMA technology
involves additives, the asphalt cement shall be graded with the asphalt
cement additive included. Copies of these certifications shall be
submitted to the Contracting Officer Engineer. The supplier is defined as
the last source of any modification to the binder. The Contracting Officer
Engineer may sample and test the binder at the mix plant at any time before
or during mix production. Samples for this verification testing shall be
obtained in accordance with ASTM D140/D140M and in the presence of the
Contracting Officer Engineer. These samples shall be furnished to the
Contracting Officer Engineer for the verification testing, which shall be
at no cost to the Contractor. Submit 20 L 5 gallon sample of the asphalt
cement specified for mix design verification and approval not less than 14
days before start of the test section.
2.3
WMA TECHNOLOGIES/PRODUCTS
WMA technologies/products shall have a record of good performance and shall
be included on the local state DOT's qualified products list, if the DOT
maintains a qualified products list. Also, the WMA technologies/products
shall be included in at least two out of the following three states DOT's
qualified products lists: Texas, Virginia and Florida. These qualified
products lists can be found at each state DOT's website.
2.4
MIX DESIGN
**************************************************************************
NOTE: Use 75 blow Marshall hand-held hammer
compaction or 75 gyration Superpave gyratory
compaction for all pavements designed for tire
pressures of 690 kPa 100 psi or higher.
Use 50 Blow Marshall hand-held hammer compaction or
50 gyration Superpave gyratory compaction for all
shoulder pavements and pavements designed for tire
pressures less than 690 kPa 100 psi.
For Marshall mixes, delete the column in Table 6
which does not apply, unless the project includes
both 75 Blow and 50 Blow mixes.
SECTION 32 12 15.16
Page 24
Table 8. Action and Suspension Limits for the Parameters to be Plotted on Individual
and Running Average Control Charts
Individual Samples
Parameter to be Plotted
Running Average of Last Four
Samples
Action
Limit
Suspension
Limit
0.4
0.5
Asphalt content, percent
deviation from JMF target;
plus or minus value
Action Limit Suspension Limit
0.2
0.3
Laboratory Air Voids, percent
No specific action and suspension limits set since
deviation from JMF target value this parameter is used to determine percent payment
In-place Mat Density, percent
of TMD
No specific action and suspension limits set since
this parameter is used to determine percent payment
In-place Joint Density,
percent of TMD
No specific action and suspension limits set since
this parameter is used to determine percent payment
TSR, percent minimum
73
70
Gradation 1
13.3
13.0
13.5
13.0
Gradation 2
14.3
14.0
14.5
14.0
Gradation 3
15.3
15.0
15.0
15.0
VMA
Table 8 cont'd.
Marshall Compaction
Stability, N pounds (minimum)
75 blow JMF
78301760
72901640
95602150
90302030
50 blow JMF
4230950
3690830
60001350
54701230
8 min.
7 min.
9 min.
8 min.
16 max.
17 max.
15 max.
16 max.
8 min.
7 min.
9 min.
8 min.
18 max.
19 max.
17 max.
18 max.
Flow, 0.25 mm 0.01 inches
75 blow JMF
50 blow JMF
SECTION 32 12 15.16
Page 33
3.2
PREPARATION OF ASPHALT BINDER MATERIAL
The asphalt cement material shall be heated avoiding local overheating and
providing a continuous supply of the asphalt material to the mixer at a
uniform temperature. The temperature of asphalt binder shall be no more
than 132 degrees C 270 degrees F when added to the aggregates.
3.3
PREPARATION OF MINERAL AGGREGATE
The aggregate for the mixture shall be heated and dried prior to mixing.
No damage shall occur to the aggregates due to the maximum temperature and
rate of heating used. The temperature of the aggregate and mineral filler
shall not exceed 132 degrees C 270 degrees F when the asphalt binder is
added. The temperature shall not be lower than is required to obtain
complete coating and uniform distribution on the aggregate particles and to
provide a mixture of satisfactory workability.
3.4
PREPARATION OF WARM-MIX ASPHALT MIXTURE
The aggregates, asphalt cement, and WMA additives, if added separately at
the plant, shall be weighed or metered and introduced into the mixer in the
amount specified by the JMF. The combined materials shall be mixed until
the aggregate obtains a thorough and uniform coating of asphalt binder
(testing in accordance with ASTM D2489/D2489M may be required by the
Contracting Officer) and is thoroughly distributed throughout the mixture.
The moisture content of all WMA upon discharge from the plant shall not
exceed 0.5 percent by total weight of mixture as measured by ASTM D1461.
3.5
PREPARATION OF THE UNDERLYING SURFACE
**************************************************************************
NOTE: If the underlying surface to be paved is an
unbound granular layer, a prime coat should be
applied, especially if this layer will be exposed to
weather for an extended period of time prior to
covering with an asphalt mixture. Benefits derived
from a prime coat include an additional
weatherproofing of the base, improving the bond
between the base and WMA layer, and preventing the
base from shifting under construction equipment. If
the prime coat requirement is not a separate pay
item and is waived from this contract, an adjustment
to the contract price should be made. Environmental
laws in certain states may not allow prime coats to
be applied.
If the underlying surface to be paved is an existing
asphalt or concrete layer, a tack coat should always
be used to ensure an adequate bond between layers.
Tack and prime coat requirements will need to be
covered in the contract documents.
**************************************************************************
Immediately before placing the WMA, the underlying course shall be cleaned
of dust and debris. A [prime coat] [and/or] [tack coat] shall be applied
in accordance with the contract specifications.
SECTION 32 12 15.16
Page 34
Table 6.
Marshall Design Criteria
Test Property
75 Blow Mix
50 Blow Mix
(4) Select the JMF asphalt content corresponding to an air void content of 4
percent. Verify the other properties of Table 6 meet the specification
requirements at this asphalt content.
Table 6.
Superpave Gyratory Compaction Criteria
Test Property
Value
4(1)
Air voids, percent
Percent Voids in mineral aggregate
(minimum)
See Table 7
Dust Proportion(2)
0.8-1.2
TSR, minimum percent
75
(1) Select the JMF asphalt content corresponding to an air void content of 4
percent. Verify the other properties of Table 6 meet the specification
requirements at this asphalt content.
(2) Dust Proportion is calculated as the aggregate content, expressed as a
percent of mass, passing the 0.075 mm No. 200 sieve, divided by the effective
asphalt content, in percent of total mass of the mixture.
Table 7.
Minimum Percent Voids in Mineral Aggregate (VMA)(1)
Aggregate (See Table 5)
Minimum VMA, percent
Gradation 1
13
Gradation 2
14
Gradation 3
15
(1) Calculate VMA in accordance with AI MS-2, based on ASTM D2726/D2726M bulk
specific gravity for the aggregate.
2.4.2
Adjustments to JMF
The JMF for each mixture shall be in effect until a new formula is approved
in writing by the Contracting Officer Engineer. Should a change in sources
of any materials be made, a new mix design shall be performed and a new JMF
approved before the new material is used. The Contractor will be allowed
to make minor adjustments within the specification limits to the JMF to
optimize mix volumetric properties. Adjustments to the original JMF shall
be limited to plus or minus 4 percent on the 4.75 mm No. 4 and coarser
sieves; plus or minus 3 percent on the 2.36 mm No. 8 to 0.30 mm No. 50
sieves; and plus or minus 1 percent on the 0.15 mm No. 100 sieve.
Adjustments to the JMF shall be limited to plus or minus 1.0 percent on the
0.075 mm No. 200 sieve. Asphalt content adjustments shall be limited to
plus or minus 0.40 from the original JMF. If adjustments are needed that
SECTION 32 12 15.16
Page 27
exceed these limits, a new mix design shall be developed.
2.5
RECYCLED WMA
**************************************************************************
NOTE: Reclaimed Asphalt Pavement (RAP) should not
be used for surface mixes, except on shoulders. It
can be used very effectively in lower layers, or for
shoulders. The Contractor should be able to use
RAP, up to 30 percent, as long as the resulting
recycled mix meets all requirements that are
specified for virgin mixtures. Remove these
paragraphs if RAP is not used.
**************************************************************************
Recycled WMA shall consist of reclaimed asphalt pavement (RAP), coarse
aggregate, fine aggregate, mineral filler, and asphalt cement. The RAP
shall be of a consistent gradation and asphalt content and properties. RAP
stockpiles shall be free from contamination, including coal-tar sealers.
When RAP is fed into the plant, the maximum RAP chunk size shall not exceed
50 mm 2 inches. The individual aggregates in a RAP chunk shall not exceed
the maximum size aggregate of the gradation specified in Table 6. The
recycled WMA mix shall be designed using procedures contained in AI MS-2.
The job mix shall meet the requirements of paragraph MIX DESIGN. RAP shall
only be used for shoulder surface course mixes and for any intermediate
courses. The amount of RAP shall be limited to 30 percent.
2.5.1
RAP Aggregates and Asphalt Cement
The blend of aggregates used in the recycled mix shall meet the
requirements of paragraph AGGREGATES. The percentage of asphalt in the RAP
shall be established for the mixture design according to ASTM D2172/D2172M
using the appropriate dust correction procedure.
2.5.2
RAP Mix
**************************************************************************
NOTE: The appropriate test should be selected to
conform to the grade of new asphalt specified. If a
penetration grade is specified, use penetration
test. If a viscosity grade is specified, use a
viscosity test. If a PG asphalt binder is
specified, use the dynamic shear rheometer and
bending beam tests.
**************************************************************************
The blend of new asphalt cement and the RAP asphalt binder shall meet the
[penetration] [viscosity] requirements in paragraph ASPHALT CEMENT BINDER.
For PG graded asphalt binders, adjust as follows:
a.
a.
For 0-20 percent recycled binder content - no change in virgin
binder selection.
b.
For 20+ to 30 percent recycled binder content - select virgin binder
one grade softer than normal.
SECTION 32 12 15.16
Page 28
a.
Pave the WMA side of the joint in a direction parallel to the joint.
b.
Place the WMA side sufficiently high so that when fully compacted the
WMA will be greater than 3 mm 1/8 inch but less than 6 mm 1/4 inch
higher than the PCC side of the joint.
c.
Compaction shall be provided with steel wheel rollers and at least one
rubber tire roller. The rubber tire roller shall be at least 18 metric
tons 20 tons in weight and have tires that are inflated to at least 620
kPa 90 psi. Avoid spalling the PCC during placement and compaction of
the WMA. Steel wheel rollers shall be operated in a way that prevents
spalling the PCC. Any damage to PCC edges or joints shall be repaired
as directed by the Contracting OfficerEngineer. If damage to the PCC
joint or edge exceeds a total of 1 m 3 feet, the PCC panel shall be
removed and replaced at no additional expense to the Government.
d.
After compaction is finished the WMA shall be leveled by grinding so
that the WMA side is less than 3 mm 1/8 inch higher than the PCC side.
The WMA immediately adjacent to the joint shall not be lower than the
PCC after the grinding operation. Transition the grinding into the WMA
in a way that ensures good smoothness and provides drainage of water.
The joint and adjacent materials when completed shall meet all of the
requirements for grade and smoothness. Measure smoothness across the
PCC-WMA joint using a 4 m 12 feet straightedge. The acceptable
tolerance is 3 mm 1/8 inch.
e.
Consider the WMA next to the PCC as a separate lot for evaluation.
Lots are based on individual lifts. Do not comingle cores from
different lifts for density evaluation purposes. Take four cores for
each lot of material placed adjacent to the joint. The size of lot
shall be 3 m 10 feet wide by the length of the joint being paved. Lots
are based on individual lifts and shall not be comingled for density
evaluation purposes. Locate the center of each of the four cores 150 mm
6 inches from the edge of the concrete. Take each core at a random
location along the length of the joint. The requirements for density
for this lot, adjacent to the joint, are the same as that for the mat
specified earlier.
f.
All procedures, including repair of damaged PCC, shall be in accordance
with the approved Quality Control Plan.
-- End of Section --
SECTION 32 12 15.16
Page 39
the Contractor in writing of any noted deficiencies concerning the
laboratory facility, equipment, supplies, or testing personnel and
procedures. When the deficiencies are serious enough to adversely affect
test results, the incorporation of the materials into the work shall be
suspended immediately and will not be permitted to resume until the
deficiencies are corrected.
3.1.3
Quality Control Testing
Perform all quality control tests applicable to these specifications and as
set forth in the Quality Control Program. The testing program shall
include, but shall not be limited to, tests for the control of asphalt
content, aggregate gradation, temperatures, aggregate moisture, moisture in
the asphalt mixture, laboratory air voids, stability, flow, in-place
density, grade and smoothness. A Quality Control Testing Plan shall be
developed as part of the Quality Control Program.
3.1.3.1
Asphalt Content
A minimum of two tests to determine asphalt content will be performed per
lot (a lot is defined in paragraph QUALITY ASSURANCE) by one of the
following methods: extraction method in accordance with ASTM D2172/D2172M,
Method A or B, the ignition method in accordance with the AASHTO T 308,
ASTM D6307, or the nuclear method in accordance with ASTM D4125/D4125M,
provided each method is calibrated for the specific mix being used. For
the extraction method, the weight of ash, as described in ASTM D2172/D2172M,
shall be determined as part of the first extraction test performed at the
beginning of plant production; and as part of every tenth extraction test
performed thereafter, for the duration of plant production. The last
weight of ash value obtained shall be used in the calculation of the
asphalt content for the mixture.
3.1.3.2
Aggregate Properties
Aggregate gradations shall be determined a minimum of twice per lot from
mechanical analysis of recovered aggregate in accordance with ASTM D5444 or
ASTM D6307. For batch plants, aggregates shall be tested in accordance
with ASTM C136/C136M using actual batch weights to determine the combined
aggregate gradation of the mixture. The specific gravity of each aggregate
size grouping shall be determined for each 18,000 metric tons 20,000 tons
in accordance with ASTM C127 or ASTM C128. Fractured faces for gravel
sources shall be determined for each 18,000 metric tons 20,000 tons in
accordance with COE CRD-C 171. The uncompacted void content of
manufactured sand shall be determined for each 18,000 metric tons 20,000
tons in accordance with ASTM C1252 Method A.
3.1.3.3
Temperatures
Temperatures shall be checked at least four times per lot, at necessary
locations, to determine the temperature at the dryer, the asphalt cement in
the storage tank, the asphalt mixture at the plant, and the asphalt mixture
at the job site.
3.1.3.4
Aggregate Moisture
The moisture content of aggregate used for production shall be determined a
minimum of once per lot in accordance with ASTM C566.
SECTION 32 12 15.16
Page 30
3.1.3.5
Moisture Content of Mixture
The moisture content of the mixture shall be determined at least twice per
lot in accordance with AASHTO T 329.
3.1.3.6
Laboratory Air Voids, VMA, Marshall Stability and Flow
Mixture samples shall be taken at least four times per lot and compacted
into specimens, [using [50] [75] blows per side with the Marshall hand-held
hammer as described in ASTM D6926.] [using [50] [75] gyrations of the
Superpave gyratory compactor as described in ASTM D6925.] After
compaction, the laboratory air voids and VMA of each specimen shall be
determined[, as well as the Marshall stability and flow, as described in
ASTM D6927].. The VMA shall be within the limits of Table 8.
3.1.3.7
Moisture Susceptibility
Determine the Tensile Strength Ratio (TSR) by ASTM D4867/D4867M for test
section production and at least once for every five lots. TSR values shall
be not less than 75 percent.
3.1.3.8
In-Place Density
Conduct any necessary testing to ensure the specified density is achieved.
A nuclear gauge or other non-destructive testing device may be used to
monitor pavement density.
3.1.3.9
Grade and Smoothness
Conduct the necessary checks to ensure the grade and smoothness
requirements are met in accordance with paragraph QUALITY ASSURANCE.
3.1.3.10
Additional Testing
Any additional testing, which the Contractor deems necessary to control the
process, may be performed at the Contractor's option.
3.1.3.11
QC Monitoring
Submit all QC test results to the Contracting Officer Engineer on a daily
basis as the tests are performed. The Contracting Officer Engineer
reserves the right to monitor any of the Contractor's quality control
testing and to perform duplicate testing as a check to the Contractor's
quality control testing.
3.1.4
Sampling
When directed by the Contracting Officer Engineer, sample and test any
material which appears inconsistent with similar material being produced,
unless such material is voluntarily removed and replaced or deficiencies
corrected by the Contractor. All sampling shall be in accordance with
standard procedures specified.
3.1.5
Control Charts
For process control, establish and maintain linear control charts on both
individual samples and the running average of last four samples for the
parameters listed in Table 8, as a minimum. These control charts shall be
posted as directed by the Contracting Officer Engineer and shall be kept
SECTION 32 12 15.16
Page 31
current at all times. The control charts shall identify the project
number, the test parameter being plotted, the individual sample numbers,
the Action and Suspension Limits listed in Table 8 applicable to the test
parameter being plotted, and the Contractor's test results. Target values
(JMF) shall also be shown on the control charts as indicators of central
tendency for the cumulative percent passing, asphalt content, and
laboratory air voids parameters. When the test results exceed either
applicable Action Limit, take immediate steps to bring the process back in
control. When the test results exceed either applicable Suspension Limit,
halt production until the problem is solved. When the Suspension Limit is
exceeded for individual values or running average values, the Contracting
Officer Engineer has the option to require the Contractor to remove and
replace the material represented by the samples or to leave in place and
base acceptance on mixture volumetric properties and in place density. Use
the control charts as part of the process control system for identifying
trends so that potential problems can be corrected before they occur.
Decisions concerning mix modifications shall be made based on analysis of
the results provided in the control charts. The Quality Control Plan shall
indicate the appropriate action which shall be taken to bring the process
into control when certain parameters exceed their Action Limits.
Table 8. Action and Suspension Limits for the Parameters to be Plotted on Individual
and Running Average Control Charts
Individual Samples
Parameter to be Plotted
Running Average of Last Four
Samples
Action
Limit
Suspension
Limit
4.75 mm No. 4 sieve,
Cumulative Percent Passing,
deviation from JMF target;
plus or minus values
6
8
4
5
0.6 mm No. 30 sieve,
Cumulative Percent Passing,
deviation from JMF target;
plus or minus values
4
6
3
4
0.075 mm No. 200 sieve,
Cumulative Percent Passing,
deviation from JMF target;
plus or minus values
1.4
2.0
1.1
1.5
SECTION 32 12 15.16
Action Limit Suspension Limit
Page 32
Table 8. Action and Suspension Limits for the Parameters to be Plotted on Individual
and Running Average Control Charts
Individual Samples
Parameter to be Plotted
Running Average of Last Four
Samples
Action
Limit
Suspension
Limit
0.4
0.5
Asphalt content, percent
deviation from JMF target;
plus or minus value
Action Limit Suspension Limit
0.2
0.3
Laboratory Air Voids, percent
No specific action and suspension limits set since
deviation from JMF target value this parameter is used to determine percent payment
In-place Mat Density, percent
of TMD
No specific action and suspension limits set since
this parameter is used to determine percent payment
In-place Joint Density,
percent of TMD
No specific action and suspension limits set since
this parameter is used to determine percent payment
TSR, percent minimum
73
70
Gradation 1
13.3
13.0
13.5
13.0
Gradation 2
14.3
14.0
14.5
14.0
Gradation 3
15.3
15.0
15.0
15.0
VMA
Table 8 cont'd.
Marshall Compaction
Stability, N pounds (minimum)
75 blow JMF
78301760
72901640
95602150
90302030
50 blow JMF
4230950
3690830
60001350
54701230
8 min.
7 min.
9 min.
8 min.
16 max.
17 max.
15 max.
16 max.
8 min.
7 min.
9 min.
8 min.
18 max.
19 max.
17 max.
18 max.
Flow, 0.25 mm 0.01 inches
75 blow JMF
50 blow JMF
SECTION 32 12 15.16
Page 33
3.2
PREPARATION OF ASPHALT BINDER MATERIAL
The asphalt cement material shall be heated avoiding local overheating and
providing a continuous supply of the asphalt material to the mixer at a
uniform temperature. The temperature of asphalt binder shall be no more
than 132 degrees C 270 degrees F when added to the aggregates.
3.3
PREPARATION OF MINERAL AGGREGATE
The aggregate for the mixture shall be heated and dried prior to mixing.
No damage shall occur to the aggregates due to the maximum temperature and
rate of heating used. The temperature of the aggregate and mineral filler
shall not exceed 132 degrees C 270 degrees F when the asphalt binder is
added. The temperature shall not be lower than is required to obtain
complete coating and uniform distribution on the aggregate particles and to
provide a mixture of satisfactory workability.
3.4
PREPARATION OF WARM-MIX ASPHALT MIXTURE
The aggregates, asphalt cement, and WMA additives, if added separately at
the plant, shall be weighed or metered and introduced into the mixer in the
amount specified by the JMF. The combined materials shall be mixed until
the aggregate obtains a thorough and uniform coating of asphalt binder
(testing in accordance with ASTM D2489/D2489M may be required by the
Contracting Officer) and is thoroughly distributed throughout the mixture.
The moisture content of all WMA upon discharge from the plant shall not
exceed 0.5 percent by total weight of mixture as measured by ASTM D1461.
3.5
PREPARATION OF THE UNDERLYING SURFACE
**************************************************************************
NOTE: If the underlying surface to be paved is an
unbound granular layer, a prime coat should be
applied, especially if this layer will be exposed to
weather for an extended period of time prior to
covering with an asphalt mixture. Benefits derived
from a prime coat include an additional
weatherproofing of the base, improving the bond
between the base and WMA layer, and preventing the
base from shifting under construction equipment. If
the prime coat requirement is not a separate pay
item and is waived from this contract, an adjustment
to the contract price should be made. Environmental
laws in certain states may not allow prime coats to
be applied.
If the underlying surface to be paved is an existing
asphalt or concrete layer, a tack coat should always
be used to ensure an adequate bond between layers.
Tack and prime coat requirements will need to be
covered in the contract documents.
**************************************************************************
Immediately before placing the WMA, the underlying course shall be cleaned
of dust and debris. A [prime coat] [and/or] [tack coat] shall be applied
in accordance with the contract specifications.
SECTION 32 12 15.16
Page 34
3.6
TEST SECTION
Prior to full production, place a test section for each JMF used.
Construct a test section consisting of a maximum of 250 tons and two paver
passes wide placed in two lanes, with a longitudinal cold joint. The test
section shall be of the same depth as the course which it represents. The
underlying grade or pavement structure upon which the test section is to be
constructed shall be the same as the remainder of the course represented by
the test section. The equipment used in construction of the test section
shall be the same equipment to be used on the remainder of the course
represented by the test section. The test section shall be placed as part
of the project pavement as approved by the Contracting Officer Engineer.
3.6.1
Sampling and Testing for Test Section
**************************************************************************
NOTE: Table 9 applies only to the test section.
The limits in Tables 1, 2, and 8, apply to a number
of tests run from a lot. This is why the limits
listed in Table 9 are different from those listed in
Tables 1, 2, and 8.
Select the appropriate VMA requirement to match the
selected gradation. Select the appropriate
stability and flow value to match the laboratory
compactive effort (50 or 75 blows).
**************************************************************************
One random sample shall be taken at the plant, triplicate specimens
compacted, and tested for stability, flow, laboratory air voids, and
Tensile Strength Ratio (TSR). A portion of the same sample shall be tested
for theoretical maximum density (TMD), aggregate gradation and asphalt
content. Four randomly selected cores shall be taken from the finished
pavement mat, and four from the longitudinal joint, and tested for
density. Random sampling shall be in accordance with procedures contained
in ASTM D3665. The test results shall be within the tolerances or exceed
the minimum values shown in Table 9 for work to continue. If all test
results meet the specified requirements, the test section shall remain as
part of the project pavement. If test results exceed the tolerances shown,
the test section shall be removed and replaced at no cost to the Government
Owner and another test section shall be constructed.
Table 9.
Test Section Requirements for Material and Mixture Properties
Property
Specification Limit
Aggregate Gradation-Percent Passing (Individual Test Result)
4.75 mm No. 4 and larger
JMF plus or minus 8
2.36, 1.18, 0.60, and 0.30 mmNo. 8, No.
16, No. 30, and No. 50
JMF plus or minus 6
0.15 and 0.075 mmNo. 100 and No. 200
JMF plus or minus 2.0
SECTION 32 12 15.16
Page 35
Table 9.
Test Section Requirements for Material and Mixture Properties
Property
Specification Limit
Asphalt Content, Percent (Individual Test
Result)
JMF plus or minus 0.5
Laboratory Air Voids, Percent (Average of
3 specimens)
JMF plus or minus 1.0
VMA, Percent (Average of 3 specimens)
See Table 8
Tensile Strength Ratio (TSR) (At 7 percent
plus/minus 1 percent air void content)
75 percent minimum
Conditioned Strength
415 kPa 60 psi minimum
Mat Density, Percent of TMD (Average of 4
Random Cores)
92.0 - 96.0
Joint Density, Percent of TMD (Average of
4 Random Cores)
90.5 minimum
Table 9. cont'd - Marshall Compaction
Stability,N
specimens)
pounds (Average of 3
Flow, 0.25 mm 0.01 inches (Average of 3
specimens)
3.6.2
[6000] [9560] [1350] [2150] minimum
[8 - 16] [8 - 18]
Additional Test Sections
If the initial test section should prove to be unacceptable, the necessary
adjustments to the JMF, plant operation, placing procedures, and/or rolling
procedures shall be made. A second test section shall then be placed.
Additional test sections, as required, shall be constructed and evaluated
for conformance to the specifications. Full production shall not begin
until an acceptable section has been constructed and accepted.
3.7
TESTING LABORATORY
**************************************************************************
NOTE: Include bracketed sentence for Corps-managed
projects.
**************************************************************************
The laboratories used to develop the JMF, perform Contractor Quality
Control testing, and for Government Engineer acceptance testing shall meet
the requirements of ASTM D3666. All required test methods shall be
performed by an accredited laboratory. [The Government will inspect the
laboratory equipment and test procedures prior to the start of WMA
operations for conformance with ASTM D3666. The laboratory shall maintain
this validation for the duration of the project.] Submit a certification
of compliance signed by the manager of the laboratory stating that it meets
these requirements to the Contracting Officer Engineer prior to the start
of construction. The certification shall contain as a minimum:
a.
Qualifications of personnel; laboratory manager, supervising
technician, and testing technicians.
SECTION 32 12 15.16
Page 36
b.
A listing of equipment to be used in developing the job mix.
c.
A copy of the laboratory's quality control system.
d.
Evidence of participation in the AASHTO Materials Reference Laboratory
(AMRL) program.
3.8
3.8.1
TRANSPORTING AND PLACING
Transporting
Transport the WMA from the mixing plant to the site in clean, tight
vehicles. Schedule deliveries so that placing and compacting of mixture is
uniform with minimum stopping and starting of the paver. Provide adequate
artificial lighting for night placements. Hauling over freshly placed
material will not be permitted until the material has been compacted as
specified, and allowed to cool to 60 degrees C 140 degrees F.
3.8.2
Placing
The mix shall be placed in lifts of adequate thickness and compacted at a
temperature suitable for obtaining density, surface smoothness, and other
specified requirements. Upon arrival, the mixture shall be placed to the
full width by an asphalt paver; it shall be struck off in a uniform layer
of such depth that, when the work is completed, it shall have the required
thickness and conform to the grade and contour indicated. Waste mixture
shall not be broadcast onto the mat or recycled into the paver hopper.
Collect waste mixture and dispose off site. The speed of the paver shall
be regulated to eliminate pulling and tearing of the asphalt mat.
Placement of the mixture shall begin along the centerline of a crowned
section or on the high side of areas with a one-way slope. The mixture
shall be placed in consecutive adjacent strips having a minimum width of 3 m
10 feet. The longitudinal joint in one course shall offset the
longitudinal joint in the course immediately below by at least 300 mm 1 foot;
however, the joint in the surface course shall be at the centerline of the
pavement. Transverse joints in one course shall be offset by at least 3 m
10 feet from transverse joints in the previous course. Transverse joints
in adjacent lanes shall be offset a minimum of 3 m 10 feet. On isolated
areas where irregularities or unavoidable obstacles make the use of
mechanical spreading and finishing equipment impractical, the mixture may
be spread and luted by hand tools.
3.9
3.9.1
COMPACTION OF MIXTURE
General
a.
After placing, the mixture shall be thoroughly and uniformly compacted
by rolling. The surface shall be compacted as soon as possible without
causing displacement, cracking or shoving. The sequence of rolling
operations and the type of rollers used are at the discretion of the
Contractor, with the exception that application of more than three
passes with a vibratory roller in the vibrating mode is prohibited.
The speed of the roller shall, at all times, be sufficiently slow to
avoid displacement of the hot mixture and be effective in compaction.
Correct at once any displacement occurring as a result of reversing the
direction of the roller, or from any other cause.
b.
Furnish sufficient rollers to handle the output of the plant. Continue
rolling until the surface is of uniform texture, true to grade and
SECTION 32 12 15.16
Page 37
cross section, and the required field density is obtained. To prevent
adhesion of the mixture to the roller, keep the wheels properly
moistened, but excessive water will not be permitted. In areas not
accessible to the roller, thoroughly compact the mixture with hand
tampers. Remove the full depth of any mixture that becomes loose and
broken, mixed with dirt, contains check-cracking, or is in any way
defective, replace with fresh hot mixture and immediately compact to
conform to the surrounding area. This work shall be done at the
Contractor's expense. Skin patching will not be allowed.
3.9.2
Segregation
The Contracting Officer Engineer can sample and test any material that
looks deficient. When the in-place material appears to be segregated, the
Contracting Officer Engineer has the option to sample the material and have
it tested and compared to the aggregate gradation, asphalt content, and
in-place density requirements in Table 10. If the material fails to meet
these specification requirements, the extent of the segregated material
will be removed and replaced the full depth of the layer of asphalt mixture
at no additional cost to the Government. When segregation occurs in the
mat, take appropriate action to correct the process so that additional
segregation does not occur.
3.10
JOINTS
The formation of joints shall be made ensuring a continuous bond between
the courses and to obtain the required density. All joints shall have the
same texture as other sections of the course and meet the requirements for
smoothness and grade.
3.10.1
Transverse Joints
The roller shall not pass over the unprotected end of the freshly laid
mixture, except when necessary to form a transverse joint. When necessary
to form a transverse joint, it shall be made by means of placing a bulkhead
or by tapering the course. The tapered edge shall be cut back to its full
depth and width on a straight line to expose a vertical face prior to
placing the adjacent lane. The cutback material shall be removed from the
project. In both methods, all contact surfaces shall be given a light tack
coat of asphalt material before placing any fresh mixture against the joint.
3.10.2
Longitudinal Joints
Longitudinal joints which are irregular, damaged, uncompacted, cold (less
than 80 degrees C 175 degrees F at the time of placing the adjacent lane),
or otherwise defective, shall be cut back a maximum of 75 mm 3 inches from
the top edge of the lift with a cutting wheel to expose a clean, sound,
near vertical surface for the full depth of the course. All cutback
material shall be removed from the project. Cutting equipment that uses
water as a cooling or cutting agent shall not be permitted. All contact
surfaces shall be given a light tack coat of asphalt material prior to
placing any fresh mixture against the joint.
3.10.3
WMA-Portland Cement Concrete Joints
Joints between WMA and PCC will require specific construction procedures
for the WMA. The following criteria are applicable to the first 3 m 10 feet
or paver width of WMA adjacent to the PCC.
SECTION 32 12 15.16
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a.
Pave the WMA side of the joint in a direction parallel to the joint.
b.
Place the WMA side sufficiently high so that when fully compacted the
WMA will be greater than 3 mm 1/8 inch but less than 6 mm 1/4 inch
higher than the PCC side of the joint.
c.
Compaction shall be provided with steel wheel rollers and at least one
rubber tire roller. The rubber tire roller shall be at least 18 metric
tons 20 tons in weight and have tires that are inflated to at least 620
kPa 90 psi. Avoid spalling the PCC during placement and compaction of
the WMA. Steel wheel rollers shall be operated in a way that prevents
spalling the PCC. Any damage to PCC edges or joints shall be repaired
as directed by the Contracting OfficerEngineer. If damage to the PCC
joint or edge exceeds a total of 1 m 3 feet, the PCC panel shall be
removed and replaced at no additional expense to the Government.
d.
After compaction is finished the WMA shall be leveled by grinding so
that the WMA side is less than 3 mm 1/8 inch higher than the PCC side.
The WMA immediately adjacent to the joint shall not be lower than the
PCC after the grinding operation. Transition the grinding into the WMA
in a way that ensures good smoothness and provides drainage of water.
The joint and adjacent materials when completed shall meet all of the
requirements for grade and smoothness. Measure smoothness across the
PCC-WMA joint using a 4 m 12 feet straightedge. The acceptable
tolerance is 3 mm 1/8 inch.
e.
Consider the WMA next to the PCC as a separate lot for evaluation.
Lots are based on individual lifts. Do not comingle cores from
different lifts for density evaluation purposes. Take four cores for
each lot of material placed adjacent to the joint. The size of lot
shall be 3 m 10 feet wide by the length of the joint being paved. Lots
are based on individual lifts and shall not be comingled for density
evaluation purposes. Locate the center of each of the four cores 150 mm
6 inches from the edge of the concrete. Take each core at a random
location along the length of the joint. The requirements for density
for this lot, adjacent to the joint, are the same as that for the mat
specified earlier.
f.
All procedures, including repair of damaged PCC, shall be in accordance
with the approved Quality Control Plan.
-- End of Section --
SECTION 32 12 15.16
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